/* Import Academic Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Crimson+Text:ital,wght@0,400;0,600;1,400&family=JetBrains+Mono:wght@400;500&display=swap');

/* CSS Custom Properties for Academic Color System */
:root {
    /* Primary Academic Palette - Inspired by prestigious institutions */
    --color-primary-900: #1a1f36;      /* Deep academic navy */
    --color-primary-800: #2d3561;      /* Rich scholarly blue */
    --color-primary-700: #405189;      /* Traditional academic blue */
    --color-primary-600: #5a6cb0;      /* Medium academic blue */
    --color-primary-500: #7c8dd6;      /* Light academic blue */
    --color-primary-400: #9fb1ec;      /* Soft academic blue */
    --color-primary-300: #c2d4ff;      /* Very light academic blue */
    --color-primary-200: #e8f0ff;      /* Pale academic blue */
    --color-primary-100: #f4f8ff;      /* Ghost academic blue */
    --color-primary-50: #fafcff;       /* Academic white */

    /* Neutral Academic Grays */
    --color-gray-900: #111827;          /* Deep charcoal */
    --color-gray-800: #1f2937;          /* Dark gray */
    --color-gray-700: #374151;          /* Medium dark gray */
    --color-gray-600: #4b5563;          /* Medium gray */
    --color-gray-500: #6b7280;          /* Neutral gray */
    --color-gray-400: #9ca3af;          /* Light gray */
    --color-gray-300: #d1d5db;          /* Very light gray */
    --color-gray-200: #e5e7eb;          /* Pale gray */
    --color-gray-100: #f3f4f6;          /* Ghost gray */
    --color-gray-50: #f9fafb;           /* Academic white */

    /* Academic Success & Error Colors */
    --color-success-600: #047857;       /* Academic green */
    --color-success-100: #d1fae5;       /* Light success */
    --color-error-600: #dc2626;         /* Academic red */
    --color-error-100: #fee2e2;         /* Light error */
    --color-warning-600: #d97706;       /* Academic amber */
    --color-warning-100: #fef3c7;       /* Light warning */

    /* Academic Typography Scale */
    --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    --font-family-serif: 'Crimson Text', Georgia, 'Times New Roman', serif;
    --font-family-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

    /* Typography Scale */
    --text-xs: 0.75rem;     /* 12px */
    --text-sm: 0.875rem;    /* 14px */
    --text-base: 1rem;      /* 16px */
    --text-lg: 1.125rem;    /* 18px */
    --text-xl: 1.25rem;     /* 20px */
    --text-2xl: 1.5rem;     /* 24px */
    --text-3xl: 1.875rem;   /* 30px */
    --text-4xl: 2.25rem;    /* 36px */
    --text-5xl: 3rem;       /* 48px */

    /* Academic Spacing Scale */
    --space-1: 0.25rem;     /* 4px */
    --space-2: 0.5rem;      /* 8px */
    --space-3: 0.75rem;     /* 12px */
    --space-4: 1rem;        /* 16px */
    --space-5: 1.25rem;     /* 20px */
    --space-6: 1.5rem;      /* 24px */
    --space-8: 2rem;        /* 32px */
    --space-10: 2.5rem;     /* 40px */
    --space-12: 3rem;       /* 48px */
    --space-16: 4rem;       /* 64px */
    --space-20: 5rem;       /* 80px */

    /* Academic Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(26, 31, 54, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(26, 31, 54, 0.1), 0 2px 4px -1px rgba(26, 31, 54, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(26, 31, 54, 0.1), 0 4px 6px -2px rgba(26, 31, 54, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(26, 31, 54, 0.1), 0 10px 10px -5px rgba(26, 31, 54, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(26, 31, 54, 0.25);

    /* Academic Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;

    /* Academic Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
}

/* Reset and Enhanced Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--text-base);
    font-weight: 400;
    line-height: 1.7;
    color: var(--color-gray-800);
    background-color: var(--color-gray-50);
    background-image: 
        radial-gradient(circle at 25px 25px, var(--color-primary-100) 2%, transparent 0%),
        radial-gradient(circle at 75px 75px, var(--color-primary-50) 1%, transparent 0%);
    background-size: 100px 100px;
    background-attachment: fixed;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Academic Sidebar Layout */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 320px;
    height: 100vh;
    background: linear-gradient(180deg, 
        rgba(255, 255, 255, 0.95) 0%, 
        rgba(250, 252, 255, 0.98) 100%);
    backdrop-filter: blur(20px);
    border-right: 1px solid var(--color-gray-200);
    box-shadow: var(--shadow-lg);
    transform: translateX(0);
    transition: all var(--transition-slow);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.sidebar::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-400) 20%, 
        var(--color-primary-600) 50%, 
        var(--color-primary-400) 80%, 
        transparent 100%);
}

.sidebar.collapsed {
    transform: translateX(-250px);
}

.sidebar-header {
    padding: var(--space-6) var(--space-6);
    border-bottom: 1px solid var(--color-gray-200);
    background: linear-gradient(135deg, 
        var(--color-primary-50) 0%, 
        rgba(255, 255, 255, 0.8) 100%);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    min-height: 80px;
}

.sidebar-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: var(--space-6);
    right: var(--space-6);
    height: 1px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-300) 50%, 
        transparent 100%);
}

.sidebar-header h2 {
    font-family: var(--font-family-serif);
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-primary-900);
    letter-spacing: -0.025em;
    line-height: 1.3;
    text-shadow: 0 1px 2px rgba(26, 31, 54, 0.1);
}

.sidebar-logo {
    height: 40px;
    width: auto;
    max-width: 200px;
    object-fit: contain;
}

.toggle-btn {
    background: var(--color-primary-50);
    border: 1px solid var(--color-primary-200);
    font-size: var(--text-lg);
    cursor: pointer;
    padding: var(--space-3);
    border-radius: var(--radius-lg);
    color: var(--color-primary-700);
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    /* Hide HTML text content and use CSS arrows */
    text-indent: -9999px;
    overflow: hidden;
    position: relative;
}

/* Default state: left arrow (collapse) */
.toggle-btn::before {
    content: '←';
    font-size: var(--text-base);
    font-weight: 700;
    line-height: 1;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    text-indent: 0;
}

.toggle-btn:hover {
    background-color: var(--color-primary-100);
    border-color: var(--color-primary-300);
    color: var(--color-primary-800);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.toggle-btn:hover::before {
    transform: translate(-50%, -50%);
}

.toggle-btn:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.toggle-btn:active::before {
    transform: translate(-50%, -50%);
}

.sidebar.collapsed .sidebar-content {
    display: none;
}

.sidebar.collapsed .sidebar-logo {
    display: none;
}

.sidebar.collapsed .toggle-btn {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: var(--color-primary-700);
    border-color: var(--color-primary-800);
    color: white;
    border-radius: var(--radius-lg);
    padding: 0;
    box-shadow: var(--shadow-xl);
    width: 44px;
    height: 44px;
    z-index: 1001;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--color-primary-800);
}

.sidebar.collapsed .toggle-btn::before {
    content: '→';
    font-size: var(--text-base);
    font-weight: 700;
    line-height: 1;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    text-indent: 0;
}

.sidebar.collapsed .toggle-btn:hover {
    background-color: var(--color-primary-800);
    border-color: var(--color-primary-900);
    transform: translateY(-50%) scale(1.05);
    box-shadow: var(--shadow-2xl);
}

.sidebar.collapsed .toggle-btn:hover::before {
    transform: translate(-50%, -50%) scale(1.1);
}

.sidebar-content {
    flex: 1;
    padding: var(--space-6);
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--color-primary-300) transparent;
}

.sidebar-content::-webkit-scrollbar {
    width: 6px;
}

.sidebar-content::-webkit-scrollbar-track {
    background: transparent;
}

.sidebar-content::-webkit-scrollbar-thumb {
    background: var(--color-primary-300);
    border-radius: var(--radius-sm);
}

.sidebar-content::-webkit-scrollbar-thumb:hover {
    background: var(--color-primary-400);
}

/* Academic Quiz Controls */
.add-quiz-btn {
    width: 100%;
    padding: var(--space-4) var(--space-5);
    background: linear-gradient(135deg, 
        var(--color-primary-600) 0%, 
        var(--color-primary-700) 100%);
    color: white;
    border: 1px solid var(--color-primary-700);
    border-radius: var(--radius-xl);
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    margin-bottom: var(--space-6);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
    letter-spacing: 0.025em;
    text-transform: uppercase;
}

.add-quiz-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent 0%, 
        rgba(255, 255, 255, 0.2) 50%, 
        transparent 100%);
    transition: left var(--transition-slow);
}

.add-quiz-btn:hover {
    background: linear-gradient(135deg, 
        var(--color-primary-700) 0%, 
        var(--color-primary-800) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary-800);
}

.add-quiz-btn:hover::before {
    left: 100%;
}

.add-quiz-btn:active {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.quiz-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.quiz-item {
    padding: var(--space-5);
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-3);
}

.quiz-item-content {
    flex: 1;
    cursor: pointer;
}

.quiz-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 100%);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.quiz-item:hover {
    background: rgba(255, 255, 255, 0.9);
    border-color: var(--color-primary-300);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.quiz-item:hover::before {
    opacity: 1;
}

.quiz-item.active {
    background: linear-gradient(135deg, 
        var(--color-primary-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    border-color: var(--color-primary-400);
    box-shadow: var(--shadow-lg);
}

.quiz-item.active::before {
    opacity: 1;
    width: 6px;
}

.quiz-item h4 {
    font-family: var(--font-family-serif);
    font-size: var(--text-base);
    font-weight: 600;
    margin-bottom: var(--space-2);
    color: var(--color-gray-900);
    line-height: 1.4;
}

.quiz-item p {
    font-size: var(--text-sm);
    color: var(--color-gray-600);
    font-weight: 500;
    opacity: 0.8;
}

/* Delete Quiz Button */
.delete-quiz-btn {
    background: none;
    border: 1px solid transparent;
    color: var(--color-gray-400);
    border-radius: var(--radius-lg);
    padding: var(--space-2);
    font-size: var(--text-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transform: scale(0.8);
}

.quiz-item:hover .delete-quiz-btn {
    opacity: 1;
    transform: scale(1);
}

.delete-quiz-btn:hover {
    background: rgba(239, 68, 68, 0.1);
    border-color: rgba(239, 68, 68, 0.3);
    color: var(--color-error-600);
    transform: scale(1.1);
}

.delete-quiz-btn:active {
    transform: scale(0.95);
    background: rgba(239, 68, 68, 0.2);
}

/* Academic Main Content Layout */
.main-content {
    margin-left: 320px;
    min-height: 100vh;
    transition: all var(--transition-slow);
    padding: var(--space-8);
    position: relative;
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.4) 0%, 
        rgba(243, 244, 246, 0.2) 100%);
}

.main-content::before {
    content: '';
    position: fixed;
    top: 0;
    left: 320px;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(122, 141, 214, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(64, 81, 137, 0.06) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(26, 31, 54, 0.03) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
    transition: left var(--transition-slow);
}

.sidebar.collapsed + .main-content {
    margin-left: 70px;
}

.sidebar.collapsed + .main-content::before {
    left: 70px;
}

/* Academic Views System */
.view {
    display: none;
    animation: fadeOut var(--transition-fast) ease-out;
}

.view.active {
    display: block;
    animation: fadeIn var(--transition-normal) ease-out;
}

/* Academic Dashboard */
.dashboard-header {
    text-align: center;
    margin-bottom: var(--space-16);
    padding: var(--space-8) 0;
    position: relative;
}

.dashboard-header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 2px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-400) 20%, 
        var(--color-primary-600) 50%, 
        var(--color-primary-400) 80%, 
        transparent 100%);
}

.dashboard-header h1 {
    font-family: var(--font-family-serif);
    font-size: clamp(var(--text-3xl), 5vw, var(--text-5xl));
    font-weight: 700;
    color: var(--color-primary-900);
    margin-bottom: var(--space-4);
    line-height: 1.25;
    letter-spacing: -0.01em;
    text-rendering: optimizeLegibility;
    /* Fallback for browsers that don't support background-clip */
    color: var(--color-primary-900);
}

/* Apply gradient only for browsers that support it */
@supports (background-clip: text) or (-webkit-background-clip: text) {
    .dashboard-header h1 {
        background: linear-gradient(135deg, 
            var(--color-primary-900) 0%, 
            var(--color-primary-700) 50%, 
            var(--color-primary-800) 100%);
        background-clip: text;
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
    }
}

.subtitle {
    font-family: var(--font-family-primary);
    font-size: var(--text-lg);
    font-weight: 400;
    color: var(--color-gray-600);
    line-height: 1.6;
    max-width: 600px;
    margin: 0 auto;
    opacity: 0.9;
}

/* Academic Statistics Cards */
.stats-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-16);
    padding: 0;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.stat-card {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    padding: var(--space-8);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-lg);
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 50%, 
        var(--color-primary-400) 100%);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: var(--shadow-2xl);
    border-color: var(--color-primary-300);
    background: rgba(255, 255, 255, 0.95);
}

.stat-card:hover::before {
    opacity: 1;
}

.stat-card h3 {
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-gray-600);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-4);
    opacity: 0.8;
}

.stat-number {
    font-family: var(--font-family-serif);
    font-size: var(--text-4xl);
    font-weight: 700;
    color: var(--color-primary-800);
    margin-bottom: var(--space-2);
    line-height: 1.2;
    text-rendering: optimizeLegibility;
    display: block;
}

/* Apply gradient only for browsers that support it well */
@supports (background-clip: text) or (-webkit-background-clip: text) {
    .stat-number {
        background: linear-gradient(135deg, 
            var(--color-primary-700) 0%, 
            var(--color-primary-900) 100%);
        background-clip: text;
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
    }
}

.stat-label {
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-gray-500);
    opacity: 0.7;
}

/* Academic Attendance Section */
.attendance-section {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    padding: var(--space-8);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.attendance-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 25%, 
        var(--color-primary-700) 50%, 
        var(--color-primary-600) 75%, 
        var(--color-primary-400) 100%);
}

.attendance-section h2 {
    font-family: var(--font-family-serif);
    font-size: var(--text-2xl);
    font-weight: 600;
    margin-bottom: var(--space-8);
    color: var(--color-primary-900);
    text-align: center;
    position: relative;
}

.attendance-section h2::after {
    content: '';
    position: absolute;
    bottom: -var(--space-4);
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 2px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-500) 50%, 
        transparent 100%);
}

.attendance-grid {
    display: grid;
    grid-template-columns: repeat(53, 1fr);
    gap: 3px;
    max-width: 100%;
    overflow-x: auto;
    padding: var(--space-4);
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.5) 0%, 
        rgba(243, 244, 246, 0.3) 100%);
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-gray-200);
}

.attendance-day {
    width: 14px;
    height: 14px;
    background-color: var(--color-gray-200);
    border-radius: var(--radius-sm);
    transition: all var(--transition-normal);
    cursor: pointer;
    position: relative;
    border: 1px solid transparent;
}

.attendance-day.completed {
    background: linear-gradient(135deg, 
        var(--color-primary-600) 0%, 
        var(--color-primary-700) 100%);
    border-color: var(--color-primary-800);
    box-shadow: 0 2px 4px rgba(64, 81, 137, 0.3);
}

.attendance-day.partial {
    background: linear-gradient(135deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-500) 100%);
    border-color: var(--color-primary-600);
    box-shadow: 0 1px 3px rgba(64, 81, 137, 0.2);
}

.attendance-day:hover {
    transform: scale(1.3);
    z-index: 10;
    box-shadow: var(--shadow-md);
}

.attendance-day.completed:hover {
    background: linear-gradient(135deg, 
        var(--color-primary-700) 0%, 
        var(--color-primary-800) 100%);
}

.attendance-day.partial:hover {
    background: linear-gradient(135deg, 
        var(--color-primary-500) 0%, 
        var(--color-primary-600) 100%);
}

/* Academic Quiz View */
.quiz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-10);
    padding: var(--space-6) 0 var(--space-8);
    border-bottom: 2px solid var(--color-gray-200);
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.8) 0%, 
        rgba(250, 252, 255, 0.6) 100%);
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    position: relative;
}

.quiz-header::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 3px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-500) 50%, 
        transparent 100%);
}

.back-btn {
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--color-gray-300);
    color: var(--color-gray-700);
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 500;
    cursor: pointer;
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    gap: var(--space-2);
    box-shadow: var(--shadow-sm);
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.95);
    border-color: var(--color-primary-300);
    color: var(--color-primary-700);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.back-btn:active {
    transform: translateY(0);
}

.quiz-progress {
    color: var(--color-gray-600);
    font-family: var(--font-family-mono);
    font-size: var(--text-sm);
    font-weight: 500;
    background: rgba(255, 255, 255, 0.6);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-gray-200);
    backdrop-filter: blur(10px);
}

/* Academic Quiz Content */
.quiz-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 var(--space-4);
}

@media (min-width: 768px) {
    .quiz-content {
        padding: 0 var(--space-6);
    }
}

.question-container {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    padding: var(--space-10);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    margin-bottom: var(--space-8);
    position: relative;
    overflow: hidden;
}

.question-container::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 25%, 
        var(--color-primary-700) 50%, 
        var(--color-primary-600) 75%, 
        var(--color-primary-400) 100%);
}

#question-text {
    font-family: var(--font-family-serif);
    font-size: var(--text-xl);
    font-weight: 600;
    margin-bottom: var(--space-8);
    color: var(--color-gray-900);
    line-height: 1.6;
    text-align: left;
    padding-left: var(--space-4);
    border-left: 3px solid var(--color-primary-300);
}

.options-container {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.option {
    padding: var(--space-5) var(--space-6) var(--space-5) var(--space-8);
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    cursor: pointer;
    transition: all var(--transition-normal);
    font-family: var(--font-family-primary);
    font-size: var(--text-base);
    font-weight: 400;
    line-height: 1.6;
    position: relative;
    overflow: visible;
    text-align: left;
    word-wrap: break-word;
    hyphens: auto;
    min-height: 60px;
    display: flex;
    align-items: center;
}

.option::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: linear-gradient(180deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 100%);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.option:hover {
    background: rgba(255, 255, 255, 0.95);
    border-color: var(--color-primary-300);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.option:hover::before {
    opacity: 1;
}

.option.selected {
    background: linear-gradient(135deg, 
        var(--color-primary-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    border-color: var(--color-primary-500);
    box-shadow: var(--shadow-lg);
    transform: translateY(-1px);
}

.option.selected::before {
    opacity: 1;
    width: 6px;
}

.option.correct {
    background: linear-gradient(135deg, 
        var(--color-success-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    border-color: var(--color-success-600);
    color: var(--color-success-600);
}

.option.correct::before {
    background: var(--color-success-600);
    opacity: 1;
    width: 6px;
}

.option.incorrect {
    background: linear-gradient(135deg, 
        var(--color-error-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    border-color: var(--color-error-600);
    color: var(--color-error-600);
}

.option.incorrect::before {
    background: var(--color-error-600);
    opacity: 1;
    width: 6px;
}

/* Academic Explanation Section */
.explanation-section {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    padding: var(--space-8);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--space-8);
    position: relative;
    overflow: hidden;
}

.explanation-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, 
        var(--color-warning-600) 0%, 
        var(--color-primary-500) 50%, 
        var(--color-warning-600) 100%);
}

.explanation-section label {
    display: block;
    font-family: var(--font-family-serif);
    font-size: var(--text-lg);
    font-weight: 600;
    margin-bottom: var(--space-4);
    color: var(--color-gray-900);
    position: relative;
    padding-left: var(--space-4);
}

.explanation-section label::before {
    content: '✍️';
    position: absolute;
    left: 0;
    top: 0;
    font-size: var(--text-base);
}

#explanation-input {
    width: 100%;
    min-height: 120px;
    padding: var(--space-5);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    font-family: var(--font-family-primary);
    font-size: var(--text-base);
    line-height: 1.6;
    resize: vertical;
    transition: all var(--transition-normal);
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    color: var(--color-gray-800);
}

#explanation-input::placeholder {
    color: var(--color-gray-500);
    font-style: italic;
}

#explanation-input:focus {
    outline: none;
    border-color: var(--color-primary-500);
    box-shadow: 0 0 0 3px rgba(122, 141, 214, 0.1);
    background: rgba(255, 255, 255, 0.95);
}

/* Academic Quiz Controls */
.quiz-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-4);
    margin-top: var(--space-8);
    padding: var(--space-4) 0;
    flex-wrap: wrap;
}

.control-btn {
    padding: var(--space-4) var(--space-6);
    border: 2px solid transparent;
    border-radius: var(--radius-xl);
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    backdrop-filter: blur(10px);
    min-width: 140px;
    min-height: 48px;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    white-space: nowrap;
}

.control-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent 0%, 
        rgba(255, 255, 255, 0.2) 50%, 
        transparent 100%);
    transition: left var(--transition-slow);
}

.control-btn.primary {
    background: linear-gradient(135deg, 
        var(--color-primary-600) 0%, 
        var(--color-primary-700) 100%);
    color: white;
    border-color: var(--color-primary-700);
    box-shadow: var(--shadow-md);
}

.control-btn.primary:hover:not(:disabled) {
    background: linear-gradient(135deg, 
        var(--color-primary-700) 0%, 
        var(--color-primary-800) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary-800);
}

.control-btn.primary:hover:not(:disabled)::before {
    left: 100%;
}

.control-btn.secondary {
    background: rgba(255, 255, 255, 0.8);
    color: var(--color-primary-700);
    border-color: var(--color-primary-300);
    box-shadow: var(--shadow-sm);
}

.control-btn.secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.95);
    border-color: var(--color-primary-400);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
    color: var(--color-primary-800);
}

.control-btn.secondary:hover:not(:disabled)::before {
    left: 100%;
}

.control-btn:active:not(:disabled) {
    transform: translateY(0);
}

.control-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.control-btn:disabled::before {
    display: none;
}

/* Academic Results View */
.results-header {
    display: flex;
    align-items: center;
    margin-bottom: var(--space-10);
    padding: var(--space-6) 0 var(--space-8);
    border-bottom: 2px solid var(--color-gray-200);
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.8) 0%, 
        rgba(250, 252, 255, 0.6) 100%);
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    position: relative;
}

.results-header::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 3px;
    background: linear-gradient(90deg, 
        transparent 0%, 
        var(--color-primary-500) 50%, 
        transparent 100%);
}

.results-header h2 {
    margin-left: var(--space-4);
    font-family: var(--font-family-serif);
    font-size: var(--text-2xl);
    font-weight: 600;
    color: var(--color-primary-900);
}

.results-content {
    max-width: 700px;
    margin: 0 auto;
    padding: 0 var(--space-4);
}

.results-summary {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    padding: var(--space-10);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    text-align: center;
    margin-bottom: var(--space-8);
    position: relative;
    overflow: hidden;
}

.results-summary::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, 
        var(--color-success-600) 0%, 
        var(--color-primary-600) 50%, 
        var(--color-success-600) 100%);
}

.result-status {
    margin-bottom: var(--space-8);
}

.status-indicator {
    display: inline-block;
    padding: var(--space-3) var(--space-6);
    border-radius: var(--radius-xl);
    font-family: var(--font-family-primary);
    font-weight: 700;
    font-size: var(--text-sm);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-6);
    border: 2px solid transparent;
    transition: all var(--transition-normal);
}

.status-indicator.pass {
    background: linear-gradient(135deg, 
        var(--color-success-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    color: var(--color-success-600);
    border-color: var(--color-success-600);
    box-shadow: 0 4px 12px rgba(4, 120, 87, 0.15);
}

.status-indicator.fail {
    background: linear-gradient(135deg, 
        var(--color-error-100) 0%, 
        rgba(255, 255, 255, 0.9) 100%);
    color: var(--color-error-600);
    border-color: var(--color-error-600);
    box-shadow: 0 4px 12px rgba(220, 38, 38, 0.15);
}

#score-display {
    font-family: var(--font-family-serif);
    font-size: var(--text-4xl);
    font-weight: 700;
    color: var(--color-primary-800);
    margin-bottom: var(--space-3);
    line-height: 1.2;
    text-rendering: optimizeLegibility;
    display: block;
}

/* Apply gradient only for browsers that support it well */
@supports (background-clip: text) or (-webkit-background-clip: text) {
    #score-display {
        background: linear-gradient(135deg, 
            var(--color-primary-700) 0%, 
            var(--color-primary-900) 100%);
        background-clip: text;
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
    }
}

#percentage-display {
    font-family: var(--font-family-primary);
    font-size: var(--text-xl);
    font-weight: 500;
    color: var(--color-gray-600);
    opacity: 0.8;
}

/* Academic Results Actions */
.results-actions {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    margin-bottom: var(--space-8);
    flex-wrap: wrap;
}

.answer-review {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    padding: var(--space-8);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.answer-review::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 50%, 
        var(--color-primary-400) 100%);
}

/* Academic Modal Design */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2000;
    backdrop-filter: blur(8px);
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
    animation: modalFadeIn var(--transition-normal) ease-out;
}

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, 
        rgba(26, 31, 54, 0.4) 0%, 
        rgba(64, 81, 137, 0.3) 100%);
    z-index: 1999;
    display: none;
}

.modal-overlay.active {
    display: block;
    animation: overlayFadeIn var(--transition-normal) ease-out;
}

.modal-content {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-2xl);
    width: 90%;
    max-width: 540px;
    max-height: 90vh;
    overflow-y: auto;
    z-index: 2001;
    position: relative;
    animation: modalSlideIn var(--transition-normal) ease-out;
}

.modal-content::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 50%, 
        var(--color-primary-400) 100%);
}

.modal-header {
    padding: var(--space-8) var(--space-8) var(--space-6);
    border-bottom: 1px solid var(--color-gray-200);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.8) 0%, 
        rgba(255, 255, 255, 0.6) 100%);
}

.modal-header h3 {
    font-family: var(--font-family-serif);
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-primary-900);
}

.close-btn {
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--color-gray-300);
    font-size: var(--text-xl);
    cursor: pointer;
    color: var(--color-gray-600);
    padding: var(--space-2);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(10px);
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.95);
    border-color: var(--color-primary-300);
    color: var(--color-primary-700);
    transform: scale(1.05);
}

.modal-body {
    padding: var(--space-8);
}

/* Academic File Upload */
.file-upload-area {
    position: relative;
    margin: var(--space-6) 0;
}

.file-upload-label {
    display: block;
    padding: var(--space-10);
    border: 2px dashed var(--color-primary-300);
    border-radius: var(--radius-xl);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.6) 0%, 
        rgba(243, 244, 246, 0.4) 100%);
    backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

.file-upload-label::before {
    content: '📄';
    font-size: var(--text-3xl);
    display: block;
    margin-bottom: var(--space-3);
    opacity: 0.7;
}

.file-upload-label:hover {
    border-color: var(--color-primary-500);
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.8) 0%, 
        rgba(243, 244, 246, 0.6) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.file-upload-label span {
    display: block;
    font-family: var(--font-family-primary);
    font-weight: 600;
    font-size: var(--text-base);
    color: var(--color-primary-700);
    margin-bottom: var(--space-2);
}

.file-upload-label small {
    color: var(--color-gray-600);
    font-size: var(--text-sm);
    opacity: 0.8;
}

#quiz-file-input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.file-preview {
    padding: var(--space-5);
    background: rgba(250, 252, 255, 0.8);
    border: 1px solid var(--color-primary-200);
    border-radius: var(--radius-xl);
    margin-top: var(--space-4);
    backdrop-filter: blur(10px);
}

/* Upload Tabs */
.upload-tabs {
    display: flex;
    gap: var(--space-2);
    margin-bottom: var(--space-6);
    border-bottom: 2px solid var(--color-gray-200);
}

.upload-tab {
    background: none;
    border: none;
    padding: var(--space-4) var(--space-6);
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-gray-600);
    cursor: pointer;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    transition: all var(--transition-normal);
    position: relative;
    border-bottom: 3px solid transparent;
}

.upload-tab:hover {
    background: rgba(250, 252, 255, 0.8);
    color: var(--color-primary-700);
}

.upload-tab.active {
    background: rgba(250, 252, 255, 0.9);
    color: var(--color-primary-800);
    border-bottom-color: var(--color-primary-600);
}

.upload-section {
    display: none;
    animation: fadeOut var(--transition-fast) ease-out;
}

.upload-section.active {
    display: block;
    animation: fadeIn var(--transition-normal) ease-out;
}

/* JSON Paste Area */
.json-paste-area {
    margin: var(--space-4) 0;
}

.json-paste-area label {
    display: block;
    font-family: var(--font-family-serif);
    font-size: var(--text-base);
    font-weight: 600;
    margin-bottom: var(--space-4);
    color: var(--color-gray-900);
}

#json-paste-input {
    width: 100%;
    min-height: 300px;
    padding: var(--space-5);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    font-family: var(--font-family-mono);
    font-size: var(--text-sm);
    line-height: 1.6;
    resize: vertical;
    transition: all var(--transition-normal);
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    color: var(--color-gray-800);
}

#json-paste-input::placeholder {
    color: var(--color-gray-500);
    font-style: normal;
    opacity: 0.8;
}

#json-paste-input:focus {
    outline: none;
    border-color: var(--color-primary-500);
    box-shadow: 0 0 0 3px rgba(122, 141, 214, 0.1);
    background: rgba(255, 255, 255, 0.95);
}

.json-validation-info {
    margin-top: var(--space-3);
    padding: var(--space-3);
    background: linear-gradient(135deg, 
        var(--color-primary-100) 0%, 
        rgba(255, 255, 255, 0.8) 100%);
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-primary-200);
}

.json-validation-info small {
    color: var(--color-primary-700);
    font-weight: 500;
}

.modal-footer {
    padding: var(--space-8);
    border-top: 1px solid var(--color-gray-200);
    display: flex;
    justify-content: flex-end;
    gap: var(--space-4);
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.6) 0%, 
        rgba(255, 255, 255, 0.4) 100%);
}

/* Mobile Top Navigation */
.mobile-top-nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1003;
    background: linear-gradient(135deg, 
        var(--color-primary-700) 0%, 
        var(--color-primary-800) 100%);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-primary-600);
    box-shadow: var(--shadow-lg);
    padding: 0 env(safe-area-inset-right, 0) 0 env(safe-area-inset-left, 0);
}

.mobile-nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4) var(--space-5);
    max-width: 100%;
}

.mobile-nav-logo {
    height: 37px; /* Increased by ~15% from 32px */
    width: auto;
    max-width: 200px; /* Slightly increased max-width too */
    margin-left: var(--space-2); /* Better alignment with left edge */
    object-fit: contain;
    filter: brightness(0) invert(1); /* Make logo white on dark background */
}

/* Help Button - Bottom Right */
.help-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1002;
    background: var(--color-primary-100);
    border: 2px solid var(--color-primary-300);
    color: var(--color-primary-700);
    border-radius: 50%;
    padding: 0;
    box-shadow: var(--shadow-lg);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    font-family: var(--font-family-primary);
    font-size: var(--text-lg);
    font-weight: 700;
}

.help-btn:hover {
    background: var(--color-primary-200);
    border-color: var(--color-primary-400);
    color: var(--color-primary-800);
    transform: scale(1.05);
    box-shadow: var(--shadow-xl);
}

.help-btn:active {
    transform: scale(0.95);
}

/* Welcome Modal */
.welcome-modal .modal-content {
    max-width: 800px;
    max-height: 90vh;
    overflow-y: auto;
}

.welcome-content {
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.98) 0%, 
        rgba(250, 252, 255, 0.95) 100%);
}

.welcome-body {
    padding: var(--space-6) var(--space-8);
}

.welcome-section {
    margin-bottom: var(--space-10);
}

.welcome-section h4 {
    font-family: var(--font-family-serif);
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--color-primary-900);
    margin-bottom: var(--space-4);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.instruction-list {
    list-style: none;
    counter-reset: step-counter;
    padding: 0;
}

.instruction-list li {
    counter-increment: step-counter;
    margin-bottom: var(--space-5);
    padding: var(--space-6);
    background: rgba(250, 252, 255, 0.8);
    border: 1px solid var(--color-primary-200);
    border-radius: var(--radius-xl);
    border-left: 4px solid var(--color-primary-500);
    position: relative;
    padding-left: 5rem; /* Fixed 80px to ensure proper clearance */
}

.instruction-list li::before {
    content: counter(step-counter);
    position: absolute;
    left: 1rem; /* Fixed 16px from left edge */
    top: var(--space-6);
    background: var(--color-primary-600);
    color: white;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: var(--text-base);
    box-shadow: var(--shadow-sm);
}

.prompt-container {
    position: relative;
    margin: var(--space-4) 0;
}

#llm-prompt {
    width: 100%;
    height: 300px;
    padding: var(--space-5);
    border: 2px solid var(--color-primary-300);
    border-radius: var(--radius-xl);
    font-family: var(--font-family-mono);
    font-size: var(--text-sm);
    line-height: 1.6;
    resize: vertical;
    background: rgba(255, 255, 255, 0.9);
    color: var(--color-gray-800);
    overflow-y: auto;
}

.copy-btn {
    position: absolute;
    top: var(--space-3);
    right: var(--space-3);
    background: var(--color-primary-600);
    border: 1px solid var(--color-primary-700);
    color: white;
    border-radius: var(--radius-lg);
    padding: var(--space-2) var(--space-4);
    font-family: var(--font-family-primary);
    font-size: var(--text-sm);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    z-index: 10;
}

.copy-btn:hover {
    background: var(--color-primary-700);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.copy-btn:active {
    transform: translateY(0);
}

.copy-btn.copied {
    background: var(--color-success-600);
    border-color: var(--color-success-600);
}

.tips-list {
    list-style: none;
    padding: 0;
}

.tips-list li {
    margin-bottom: var(--space-3);
    padding: var(--space-3) var(--space-4);
    background: rgba(250, 252, 255, 0.6);
    border: 1px solid var(--color-primary-200);
    border-radius: var(--radius-lg);
    border-left: 3px solid var(--color-primary-400);
}

.quick-start {
    background: linear-gradient(135deg, 
        var(--color-primary-100) 0%, 
        rgba(255, 255, 255, 0.8) 100%);
    border: 2px solid var(--color-primary-300);
    border-radius: var(--radius-2xl);
    padding: var(--space-6);
    text-align: center;
}

.quick-start h4 {
    justify-content: center;
}

.quick-start p {
    font-size: var(--text-base);
    color: var(--color-gray-700);
    margin: 0;
    line-height: 1.6;
}

/* Empty State Helper */
.empty-state-helper {
    margin: var(--space-8) 0;
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.9) 0%, 
        rgba(255, 255, 255, 0.7) 100%);
    border: 2px solid var(--color-primary-200);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    text-align: center;
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow-lg);
}

.empty-state-content h3 {
    font-family: var(--font-family-serif);
    font-size: var(--text-2xl);
    font-weight: 600;
    color: var(--color-primary-900);
    margin-bottom: var(--space-4);
}

.empty-state-content p {
    font-size: var(--text-lg);
    color: var(--color-gray-700);
    margin-bottom: var(--space-8);
    line-height: 1.6;
}

.empty-state-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-8);
}

.step {
    display: flex;
    align-items: flex-start;
    gap: var(--space-5);
    text-align: left;
    padding: var(--space-6);
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--color-primary-200);
    border-radius: var(--radius-xl);
    transition: all var(--transition-normal);
}

.step:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--color-primary-300);
}

.step-number {
    flex-shrink: 0;
    width: 36px;
    height: 36px;
    background: var(--color-primary-600);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: var(--text-base);
    box-shadow: var(--shadow-sm);
}

.step-content {
    flex: 1;
}

.step-content strong {
    display: block;
    font-family: var(--font-family-primary);
    font-size: var(--text-base);
    font-weight: 600;
    color: var(--color-gray-900);
    margin-bottom: var(--space-1);
}

.step-content small {
    font-size: var(--text-sm);
    color: var(--color-gray-600);
    line-height: 1.4;
}

/* Footer */
.app-footer {
    margin-top: var(--space-16);
    padding: var(--space-8) 0;
    text-align: center;
    border-top: 1px solid var(--color-gray-200);
    background: linear-gradient(135deg, 
        rgba(250, 252, 255, 0.6) 0%, 
        rgba(255, 255, 255, 0.3) 100%);
}

.app-footer p {
    margin: 0;
    font-size: var(--text-sm);
    color: var(--color-gray-600);
    font-family: var(--font-family-primary);
}

.app-footer a {
    color: var(--color-primary-700);
    text-decoration: none;
    font-weight: 600;
    transition: all var(--transition-normal);
}

.app-footer a:hover {
    color: var(--color-primary-800);
    text-decoration: underline;
}

/* Mobile Quiz Menu */
.mobile-menu-btn {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    border-radius: var(--radius-lg);
    padding: var(--space-3);
    box-shadow: var(--shadow-md);
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    flex-shrink: 0;
}

.mobile-menu-btn::before {
    content: '☰';
    font-size: var(--text-lg);
    font-weight: 700;
}

.mobile-menu-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
    box-shadow: var(--shadow-lg);
}

.mobile-menu-btn:active {
    transform: scale(0.95);
    background-color: var(--color-primary-900);
}

.mobile-quiz-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(26, 31, 54, 0.8);
    backdrop-filter: blur(8px);
    z-index: 1500;
    padding: var(--space-8);
    overflow-y: auto;
}

.mobile-quiz-overlay.active {
    display: flex;
    flex-direction: column;
    animation: fadeIn var(--transition-normal) ease-out;
}

.mobile-quiz-content {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-radius: var(--radius-2xl);
    padding: var(--space-8);
    margin-top: 80px;
    box-shadow: var(--shadow-2xl);
    border: 1px solid var(--color-gray-200);
    position: relative;
}

.mobile-quiz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-6);
    padding-bottom: var(--space-4);
    border-bottom: 2px solid var(--color-gray-200);
}

.mobile-quiz-header h2 {
    font-family: var(--font-family-serif);
    font-size: var(--text-xl);
    color: var(--color-primary-900);
    margin: 0;
}

.mobile-close-btn {
    background: rgba(255, 255, 255, 0.8);
    border: 1px solid var(--color-gray-300);
    border-radius: var(--radius-lg);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--color-gray-600);
    font-size: var(--text-lg);
}

.mobile-close-btn:hover {
    background: rgba(255, 255, 255, 0.95);
    border-color: var(--color-primary-300);
    color: var(--color-primary-700);
    transform: scale(1.05);
}

.mobile-quiz-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-4);
}

.mobile-quiz-item {
    padding: var(--space-5);
    background: rgba(255, 255, 255, 0.7);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    transition: all var(--transition-normal);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-3);
}

.mobile-quiz-item-content {
    flex: 1;
    cursor: pointer;
}

.mobile-quiz-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, 
        var(--color-primary-400) 0%, 
        var(--color-primary-600) 100%);
    border-radius: var(--radius-sm) 0 0 var(--radius-sm);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.mobile-quiz-item:hover {
    background: rgba(255, 255, 255, 0.9);
    border-color: var(--color-primary-300);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.mobile-quiz-item:hover::before {
    opacity: 1;
}

.mobile-quiz-item h4 {
    font-family: var(--font-family-serif);
    font-size: var(--text-base);
    font-weight: 600;
    margin-bottom: var(--space-2);
    color: var(--color-gray-900);
}

.mobile-quiz-item p {
    font-size: var(--text-sm);
    color: var(--color-gray-600);
    margin: 0;
}

/* Mobile Delete Button */
.mobile-delete-btn {
    opacity: 1 !important; /* Always visible on mobile for better touch interaction */
    transform: scale(1) !important;
    width: 40px;
    height: 40px;
    font-size: var(--text-xl);
}

.mobile-delete-btn:hover {
    background: rgba(239, 68, 68, 0.15);
    border-color: rgba(239, 68, 68, 0.4);
}

.mobile-add-quiz-btn {
    width: 100%;
    background: linear-gradient(135deg, 
        var(--color-primary-600) 0%, 
        var(--color-primary-700) 100%);
    border: 2px solid var(--color-primary-700);
    color: white;
    border-radius: var(--radius-xl);
    padding: var(--space-5);
    margin: var(--space-4) 0 var(--space-6) 0;
    font-family: var(--font-family-primary);
    font-size: var(--text-lg);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    box-shadow: var(--shadow-md);
}

.mobile-add-quiz-btn:hover {
    background: linear-gradient(135deg, 
        var(--color-primary-700) 0%, 
        var(--color-primary-800) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.mobile-add-quiz-btn:active {
    transform: translateY(0);
    box-shadow: var(--shadow-md);
}

.add-icon {
    font-size: var(--text-xl);
    font-weight: 300;
    width: 24px;
    height: 24px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.add-text {
    font-weight: 600;
}

/* Academic Responsive Design */
@media (max-width: 768px) {
    :root {
        --space-8: 1.5rem;
        --space-10: 2rem;
        --space-12: 2.5rem;
        --space-16: 3rem;
    }

    /* Hide sidebar completely on mobile */
    .sidebar {
        display: none;
    }
    
    /* Show mobile top navigation */
    .mobile-top-nav {
        display: block;
    }
    
    /* Enhanced mobile logo styling */
    .mobile-nav-content {
        padding: var(--space-4) var(--space-4); /* Reduce right padding for better balance */
    }
    
    .mobile-nav-logo {
        height: 40px; /* Even more prominent on smaller screens */
        margin-left: var(--space-3); /* Better visual alignment */
        max-width: 220px; /* Allow more space on mobile */
    }
    
    /* Help button stays in bottom right on mobile */
    
    /* Best Practice: Safe Area Insets for Fixed Elements */
    .main-content {
        margin-left: 0;
        padding: var(--space-4);
        /* Account for mobile navigation bar */
        padding-top: 80px;
    }
    

    
    .main-content::before {
        left: 0;
    }
    
    .sidebar.collapsed + .main-content {
        margin-left: 0;
    }
    
    .sidebar.collapsed + .main-content::before {
        left: 0;
    }
    
    .sidebar.collapsed .toggle-btn {
        left: 10px;
        top: 20px;
        transform: none;
        width: 44px;
        height: 44px;
        position: fixed;
        z-index: 1001;
        border-radius: var(--radius-lg);
    }
    
    .sidebar.collapsed .toggle-btn::before {
        content: '→';
        font-size: var(--text-base);
        font-weight: 700;
        position: absolute;
        left: 50%;
        top: 50%;
        transform: translate(-50%, -50%);
        text-indent: 0;
    }
    

    
    .dashboard-header h1 {
        font-size: clamp(var(--text-2xl), 8vw, var(--text-4xl));
    }
    
    .stats-container {
        grid-template-columns: 1fr;
        gap: var(--space-4);
        padding: 0;
    }
    
    .quiz-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-4);
        padding: var(--space-4) 0 var(--space-6);
    }
    
    .quiz-content {
        padding: 0 var(--space-2);
    }
    
    .question-container {
        padding: var(--space-6);
    }
    
    /* Hide file upload tab on mobile, show only JSON paste */
    #file-tab {
        display: none;
    }
    
    .upload-tabs {
        display: none; /* Hide entire tab bar since only paste is available */
    }
    
    #json-paste-section {
        display: block !important; /* Always show paste section on mobile */
    }
    
    #file-upload-section {
        display: none !important; /* Always hide file section on mobile */
    }
    
    /* Better spacing for instruction numbers on mobile */
    .instruction-list li {
        padding-left: 4rem; /* Fixed 64px for mobile - enough space for 32px circle */
    }
    
    .instruction-list li::before {
        left: 0.75rem; /* Fixed 12px from left edge */
        width: 32px;
        height: 32px;
        font-size: var(--text-sm);
    }
    
    /* Footer mobile adjustments */
    .app-footer {
        margin-top: var(--space-12);
        padding: var(--space-6) var(--space-4);
    }
    
    #question-text {
        font-size: var(--text-lg);
    }
    
    .quiz-controls {
        flex-direction: column;
        gap: var(--space-3);
    }
    
    .control-btn {
        width: 100%;
        min-width: auto;
        min-height: 52px;
        font-size: var(--text-base);
    }
    
    .results-actions {
        flex-direction: column;
        gap: var(--space-3);
    }
    
    .attendance-grid {
        grid-template-columns: repeat(26, 1fr);
        gap: 2px;
    }
    
    .attendance-day {
        width: 12px;
        height: 12px;
    }
    
    .modal-content {
        width: 95%;
        margin: var(--space-4);
    }
    
    .modal-header,
    .modal-body,
    .modal-footer {
        padding: var(--space-6);
    }
}

/* Academic Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeOut {
    from {
        opacity: 1;
        transform: translateY(0);
    }
    to {
        opacity: 0;
        transform: translateY(-10px);
    }
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-20px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@keyframes overlayFadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes shimmer {
    0% {
        background-position: -200px 0;
    }
    100% {
        background-position: calc(200px + 100%) 0;
    }
}

/* Enhanced Focus States for Accessibility */
*:focus {
    outline: 2px solid var(--color-primary-500);
    outline-offset: 2px;
}

.option:focus,
.control-btn:focus,
.add-quiz-btn:focus,
.quiz-item:focus {
    outline: 3px solid var(--color-primary-500);
    outline-offset: 2px;
    z-index: 10;
    position: relative;
}

/* Better keyboard navigation */
.option:focus-visible,
.control-btn:focus-visible,
.add-quiz-btn:focus-visible,
.quiz-item:focus-visible {
    outline: 3px solid var(--color-primary-600);
    outline-offset: 3px;
    box-shadow: 0 0 0 6px rgba(122, 141, 214, 0.15);
}

/* Loading state for buttons */
.control-btn.loading {
    pointer-events: none;
    opacity: 0.7;
}

.control-btn.loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    margin: auto;
    border: 2px solid transparent;
    border-top-color: currentColor;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    :root {
        --color-gray-50: #ffffff;
        --color-gray-100: #f0f0f0;
        --color-gray-200: #d0d0d0;
        --color-gray-800: #000000;
        --color-gray-900: #000000;
        --color-primary-700: #000080;
        --color-primary-800: #000060;
        --color-primary-900: #000040;
    }
}

/* Reduced Motion Accessibility */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .view.active {
        animation: none;
    }
    
    .modal.active {
        animation: none;
    }
    
    .modal-content {
        animation: none;
    }
    
    .modal-overlay.active {
        animation: none;
    }
}

/* Print Styles */
@media print {
    .sidebar,
    .toggle-btn,
    .quiz-controls,
    .modal,
    .modal-overlay {
        display: none !important;
    }
    
    .main-content {
        margin-left: 0 !important;
        padding: 0 !important;
    }
    
    body {
        background: white !important;
        color: black !important;
    }
    
    .question-container,
    .results-summary,
    .stat-card {
        box-shadow: none !important;
        border: 1px solid #000 !important;
    }
}